High and low water alarm apparatus.



G. W. WALSH.

HIGH AND LOW WATER ALARM APPARATUS.

APPLICATION FILED AUG.30,1011.

1,072,062. Patented Sept. 2, 1913.

GEORGE W. WALSH, OF BOSTON, MASSACHUSETTS.

HIGH AND LOW WATER ALARM APPARATUS.

Specification of Letters Patent.

Patented Sept. 2, 1 913.

Application filed August 30, 1911. Serial No. 646,920.

To all whom it may concern:

Be it known that I, GEORGE W. WALSH, a citizen of the United States, and resident of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and useful Improvement in High and Low \Vater Alarm Apparatus, of which the following is a specification.

My invention relates to high and low Water alarm apparatus for steam boilers, and its object is to provide such an apparatus which does not depend upon weights, springs, levers, etc., for its operation, but upon the expansion and contraction of a steam-carrying pipe.

One embodiment of my invention is shown in the drawing which accompanies and forms a part of this specification, the figure showing my improvement in elevation and partly in section.

In the particular drawing selected for more fully explaining the principle of my invention 1 represents the usual water column provided with gages 2, 3 and 1. Attached to the Water column by the brackets 5, 5 is a standard 6, carrying the tubes 7, 8 of any suitable material such as brass which has a fairly high coeflicient of expansion. The lower end of the thermostat pipes 7, 8 are connected with the water column by the tubes 6 7 respectively, the tube 6 entering said water column at the level 01" the gage 2, and the tube 7 entering the same at the level of the gage 1. The upper ends of the thermostat pipes are provided with flat-headed adjusting screws 9, 1O respectively.

11, 12 represent steam-operated alarm apparatus shown in the present case as steam whistles. The whistle 11 which is the high water level alarm device preferably has a high pitch and the low water level alarm whistle 12 preferably has a low pitch. The alarms being different in tone, specific and distinctive notice is given at a distance of the particular trouble, so that the appropriate remedy may be applied.

The valves 13, 1 1 connect the whistles with the T joint 16, which in turn is connected with the boiler by the pipe 15. The inner ends of the valves 13, 14 being exteriorly threaded are secured directly to the T-joint 16, without requiring the use of connecting pipes or nipples and thus preventing any springing oi the valves which otherwise would result trom the pressure exerted thereon by the expansion of the pipes 7, 8.

When the apparatus is in normal condition, the pipe 7 carries live steam and is under expansion. The adjusting screw 10 is then arranged so as to cause the valve head 13' to rest upon its seat, thereby cutting on" steam from pipe 15 to the whistle 11. On the other hand, the pipe 8 is filled with water and therefore is under a certain amount of contraction or else has its normal length. The valve head 14, which it will be noted is arranged oppositely from valve 13, is on its seat and consequently cuts ofi' steam from pipe 15 to whistle 12. The adjusting screw 9 is so arranged that when the water in the water column falls below gage 2, and steam enters the pipe 8, the expansion of the latter will open the valve 1 1 and thereby cause the whistle 12 to blow. When the water in the water column rises above the gage 1, the steam in the pipe 7 condenses and water takes its place, thereby causing the pipe 7 to contract, the valve 13 to open and the whistle 11 to sound an alarm. Both valves are operated upon directly by the expansible members which cooperate respectively with the valve stems. The valve 13 is closed by the direct action of the pipe 7, and is opened by its own weight and the pressure of the steam on the same while valve 14; is opened by the direct act-ion of the pipe 8, and is closed by its own weight and the pressure of the steam thereon.

The adjusting screw 10 which cooperates with the stem of valve 13 must be set to regulate the length of the expansible member 7 in accordance with the different tem peratures due to varying steam pressures. For a given steam pressure and temperature it is set to force the valve head 13 on its seat with sufiicient pressure to prevent leakage of steam from the pipe 15 to the whistle 11. The setting of the screw 10 governs the time at which the valve opens after the water in the water-column 1 has risen above the gage 4. Similarly, the adjusting screw 9, which cooperates with the stem of the valve 14 must be set to regulate the length of the expansible member 8 in accordance with the different temperatures due to varylow water level alarms for boilers have de.

pended for their operation upon such movreliable and easily put out of adjustment. In the present invention I control the alarm devices directly by the thermostats, thereby overcoming the difficulties formerly experienced with apparatus of this character.

lVhile I have specifically described one form of my invention it will be understood and means for adjusting the length of said I members. 5

2. In a high and low Water alarm apparatus for steam boilers, the combination with two pipes of eXpansible material adapted for connection respectively with a boiler at the low and high water levels thereof, of two alarm devices, each arranged to be opj erated by a different one of said pipes, and

' Copies oi this patent maybe obtained. for five cents each, by addressing the Commissioner of Patents,

means for adjusting the lengths of said pipes respectively. y 1

'3. In a high and low water alarm apparatus for steam boilers, the combination with two eXpansible members adapted for connection respectively with a boiler at the i low and high water levels thereof, of two alarm devices, two normally closed valves .for controlling said alarm devices respectively, one of said'valves being closed normally by the expansion of one of said members and arranged to be opened by its own ing parts as levers, weights, springs, etc, f weight and the pressure of the steam on the which have been found in practice to be unsame upon the contraction of its cobperating expansible member, and the other of said valves being normally closed by its. own weight and the pressure of" the steam on the same and arranged to be opened by the exansion of its coiiperating eXpansible memer. s

4:. In a high and low water alarm apparatus for steam boilers, the combination with two expansible members adapted for connection respectively with a boiler" at the low and high water levels thereof, of two alarm devices and two norm-ally closed valves for controlling said alarm devices respectively, said valves being so arranged that when closed there 1s no steam pressure on their stems, but only on the heads there- I of, one of said valves beingnormally closed by the expansion of its cobperating expansible member and the other by its own weight and the pressure of the steam on the same.

In testimony whereof, I have hereunto subscribed my name this 29 day of Aug.

GEORGE W. WALSH. Witnesses.

PATRICK J CoNRoY, GEO. D- WOODWORTH.

Washington, 10.0.

New 

